1. Field of the Invention
The present invention relates generally to the computation of the arctangent of a number and, more particularly, is concerned with a unique combination of electronic digital hardware for implementing a novel technique for solving the arctangent of a number in a simple and fast manner.
2. Description of the Prior Art
In many technical applications, examples of which are navigation and radar positioning, the rectangular coordinates of the position of an object in relation to a reference position and the tangent of the angle defined by the coordinates relative to a reference plane and the reference position can be readily obtained. However, difficulty is encountered in being able to quickly find the angle itself, i.e., computing the arctangent of the tangent of the angle.
One method which has been employed in the past is the Cordic trigonometric computing technique, an understanding of which may be gained by reference to the following articles:
1. "The Cordic Trigonometric Computing Technique," J. E. Volder, IRE Transactions on Electronic Computers, Vol EC-8, No. 3, pp. 330-334, September 1959. PA1 2. "A Unified Algorithm for Elementary Functions," J. S. Walther, Spring Joint Computer Conference, pp. 379-385, 1971.
Although the Cordic technique by utilizing electronic digital technology has fostered the rapid solution of arctangent computations, it has considerable drawbacks in view of its complexity and cost, and the amount of time taken to reach the solution.